Even Mormon girls who marry non-Mormons want great dads for their kids, and they are oriented to having kids, sometimes many kids.
This was the biggest one for me. Would you rather give up the prospect of being married in the temple, the assurance of children being raised in the church, and parts of Mormon culture for your boyfriend, or a great man for your beliefs.
They seriously have movies about it.
This is how I felt when I married my exmo husband.